This section provides background information related to the present disclosure which is not necessarily prior art. Example embodiments will now be described more fully with reference to the accompanying drawings. As indicated above, processes for preparing floor underlayment, such as medium density floor underlayment, are known to those skilled in this art.
Textile pads are widely used in flooring applications. A pad is desirable when wood flooring is applied over sub flooring. These pads used in flooring applications serve multiple purposes. They may absorb impact, such as from persons walking on the flooring. They may provide sound deadening, and may provide insulating properties against heat transfer. Pads also may accommodate roughness, unevenness, or other flaws in the sub flooring, and may provide a barrier against moisture and dirt. Finally, pads may lessen impact stresses on the flooring to lengthen the life of the flooring and make the flooring appear to be more durable and of a higher quality. Traditionally, these pads are formed when fibers of various sizes and materials are mixed and bound together. The binding can occur using know techniques such as needling or by the use of meltable binder fibers such as polypropylene. These techniques, while functional have several disadvantages which lead to slow throughput, high energy and cost, and environmental emissions.
As stated above, the teachings herein broadly relates to forming textile fiber matt, and particularly medium density fiber matt. Processes for production of medium density fiber matt are well known to the skilled artisan and include the blowline addition of isocyanate binders. Such a process is described, generally, below.